Electrochemical impedance spectroscopy of a porous graphite electrode used for Li-ion batteries with EC/PC based electrolytes

Abstract

Electrochemical impedance spectroscopy has been employed to investigate different electrolyte compositions used for lithium-ion batteries. Diffusion coefficients in ethylene carbonate (EC) was estimated to be in order of 10-7-10-11 cm2/s, depending on the state of charge (SOC), and propylene carbonate (PC) based electrolytes has been estimated to be in the order 10-10-10-11 cm2/s. Lithium bis(oxalato) borate (LiBOB) was used as an additive in the PC electrolytes to prevent exfoliation.